Subsea sensor assemblies

ABSTRACT

Integrated penetrator and proximity sensor probe assemblies are provided for monitoring a position of a rotating target within a subsea rotating device such as subsea motors and pumps. The integrated penetrator and proximity sensor probe assemblies are configured to communicate information related to the position of the rotating target through a wall of the device housing, and can be inserted through an opening in the wall of the device housing and mounted to the wall of the device to position a proximity sensor tip assembly adjacent the rotating target. The proximity sensor probe assemblies are pressure-compensated and configured to withstand subsea pressures and conditions.

RELATED APPLICATIONS

This application contains subject matter related to co-pending patentapplications including U.S. patent application Ser. No. ______ filedherewith, entitled “Subsea Sensor Assemblies,” and U.S. patentapplication Ser. No. ______ filed herewith, entitled “Subsea SensorAssemblies,” each of which is incorporated by reference herein in itsentirety.

BACKGROUND OF THE INVENTION

1. Field of the Invention

This present invention relates to sensor assemblies operable in harshenvironments such as high-pressure subsea applications. In particular,the invention relates to proximity sensor probes operable to monitor theperformance of rotating equipment such as subsea pumps and motorassemblies installed in an underwater fluid extraction well.

2. Description of the Related Art

In many subsea fluid extraction wells, equipment such as rotary motorsare positioned at the sea floor or at a down-hole location to controlthe production and delivery of hydrocarbons to the sea surface. Much ofthis equipment is subject to wear, and therefore needs to be repaired orreplaced periodically. Since the condition in which this equipmentoperates varies greatly from application to application, and since everysituation is unique, proper maintenance intervals can be difficult topredict. When proper maintenance intervals are underestimated, equipmentfailure and an associated emergency halt in production often results.

To help assess the need for maintenance, various sensor assemblies havebeen provided to monitor indirect parameters related to equipment healthsuch as temperature, pressure and flow rates. In one exampleapplication, accelerometers mounted to a motor case indirectly monitor amotor shaft by monitoring movement of the motor case that may have beencaused by an unbalance or vibration of the motor shaft. Often, thismethod is not very accurate. At least since the environmental conditionsencountered in subsea fluid extraction wells are generally unique foreach application, a problematic accelerometer data pattern may not beimmediately recognized. Also, since the motor case is generally muchheavier than motor shaft, small variations in the movement of the motorshaft induce even smaller variations in the movement of the motor case.Thus, in some instances, problematic movements of the motor shaft arenot recognized in the early stages and persist until the movementsbecome more pronounced. This delay can be associated with poordiagnostic information.

One application in which indirect monitoring can provide poor diagnosticinformation is in a subsea booster pump that employs fluid filmbearings. Fluid film bearings generally support their loads on a thinlayer of liquid or gas, and are frequently used in high load or highspeed applications where ball bearings would wear quickly or causeexcessive noise or vibration. In some instances, fluid film bearingspermit a motor shaft to rotate in an off-center or elliptical orbit whenproperly operating, and these orbits can be difficult to distinguishfrom problematic rotational patterns using indirect methods such asdetecting a problematic acoustic signature.

Accordingly, recognized is the need for directly monitoring a motorshaft for assessing the health of the motor used in subsea applications.Direct monitoring of a motor shaft can include monitoring dynamic motionparameters such as vibrational amplitude, frequency and phase angle, aswell as static, quasi-static or steady state position measurements suchas steady state eccentricity position, axial thrust position andeccentricity slow roll. Other parameters of a motor shaft can bedirectly monitored to facilitate assessing motor health. Also recognizedis the need for providing such a sensor assembly that can be readilyinstalled into existing motor assemblies to directly monitor the motorshaft in a variety of configurations and orientations.

SUMMARY OF THE INVENTION

In view of the foregoing, various embodiments of the present inventionadvantageously provide sensor assemblies for monitoring operationalcharacteristics of subsea pumps, motors and other rotating devices.Various aspects of the present invention advantageously provideproximity sensor assemblies that are operable to directly detect theposition of a rotating shaft without physical contact with the shaft.Proximity sensors typically actively emit RF (radio-frequency)radiation, light, sound, or other types of energy, and detect changes inthe electromagnetic field or return signal. Proximity sensor assembliesin accordance with embodiments of the present invention are configuredto withstand pressures of 1035 bar or more, as well as other subseaenvironmental conditions. Embodiments of the present invention aresufficiently flexible and adjustable to provide an EC (eddy current)sensor cap or similar proximity sensor tip adjacent a motor shaft in avariety of motor configurations. Various aspects of the presentinvention permit monitoring of subsea or other harsh environmentequipment in accordance with standards API 670 and API 610, whichgenerally apply to industrial topside machinery.

According to one aspect of the invention, a rotating device operable inhigh pressure environments includes a device housing having an openingextending through a wall of the device housing and a rotating shaft atleast partially disposed within the device housing such that an internalcavity is defined between the device housing and the rotating shaft. Therotating device also includes at least one integrated penetrator andproximity sensor probe assembly operable to monitor a position of therotating shaft with respect to a preselected reference position. The atleast one integrated penetrator and proximity sensor probe assemblyincludes a proximal penetrator housing disposed adjacent the opening inthe wall of the device housing, forming a seal with the wall of thedevice housing about the opening, and coupled to an exterior of thedevice housing. A distal penetrator housing extending from the proximalpenetrator housing into the internal cavity. A pressure-compensatedproximity sensor tip assembly is disposed within the internal cavity andcoupled to the distal penetrator housing. The proximity sensor tipassembly has interior portions into which a portion of an environmentalpressure within the internal cavity is transmissible, and includes aproximity sensor cap at an end thereof The proximity sensor tip assemblyincludes a proximity sensor cap at an end thereof and a sensing elementdisposed at least partially within the proximity sensor cap. The sensingelement is configured to produce a signal indicative of a distancebetween a reference point on the proximity sensor tip assembly andportion of the rotating shaft. A signal transmission medium isoperatively coupled to the sensing element disposed within the proximitysensor cap and extends through the distal penetrator housing, theproximal penetrator housing and the opening in the wall of the devicehousing to the exterior of the device housing to transmit the signalindicative of the distance between the reference point on the proximitysensor tip assembly and the reference point on the rotating shaft tothereby measure a position of the rotating shaft relative to apreselected reference position.

According to another aspect of the present invention, an integratedpenetrator and proximity sensor probe assembly is operable to monitor aposition of a rotating target within a device housing and to communicateinformation related to the position through a wall of the devicehousing. The integrated penetrator and proximity sensor probe assemblyincludes a proximal penetrator housing configured to form a seal with awall of the device housing about an opening extending through the wallof the device housing. The proximal penetrator housing is operable tocouple to an exterior of the device housing. A distal penetrator housingextends from the proximal penetrator housing. A proximity sensor tipassembly is coupled to an end of the distal penetrator housing oppositethe proximal penetrator housing, and the proximity sensor tip assemblyincludes a proximity sensor cap at an end thereof and a sensing elementdisposed at least partially within the proximity sensor cap. The sensingelement is configured to produce a signal indicative of a distancebetween a reference point on the proximity sensor tip assembly and aportion of the rotating target. A signal transmission medium isoperatively coupled to the sensing element disposed within the proximitysensor cap and extends through the distal penetrator housing to theproximal penetrator housing to transmit the signal indicative of thedistance to the proximal penetrator housing. An electronics package isdisposed within the proximal penetrator housing and is communicativelycoupled to the signal transmission medium. The electronics package isoperable to receive the signal indicative of the distance and operableto communicate information related to the distance to equipment exteriorto the integrated penetrator and proximity sensor probe assembly.

BRIEF DESCRIPTION OF THE DRAWINGS

So that the manner in which the features and advantages of theinvention, as well as others which will become apparent, may beunderstood in more detail, a more particular description of theinvention briefly summarized above may be had by reference to theembodiments thereof which are illustrated in the appended drawings,which form a part of this specification. It is to be noted, however,that the drawings illustrate only various embodiments of the inventionand are therefore not to be considered limiting of the invention's scopeas it may include other effective embodiments as well.

FIG. 1 is an environmental view of a subsea motor assembly with aplurality of penetrator assemblies extending through a motor housing ofthe motor assembly, according to an example embodiment of the presentinvention;

FIG. 2 is a partial environmental view of subsea pump assembly includingan integrated penetrator and sensor assembly in accordance with anembodiment of the present invention;

FIG. 3 is a partial environmental view of subsea pump assembly includinga pair of proximity sensor assemblies in accordance with an alternateembodiment of the present invention

FIG. 4A is a schematic view of a subsea penetrator assembly with anadjustable-length proximity sensor probe assembly integrated therewithaccording to an embodiment of the present invention;

FIG. 4B is an enlarged, cross-sectional view of the area of interestidentified in FIG. 4A illustrating a diaphragm or pliable membrane ofthe sensor probe assembly according to an embodiment of the presentinvention;

FIG. 4C is an enlarged cross-sectional view of the area of interestidentified in FIG. 4A illustrating an interior portion of a proximitysensor tip assembly according to an embodiment of the present invention;

FIG. 4D is a cross-sectional view of an alternate pliable membraneaccording to an embodiment of the present invention;

FIG. 5 is a schematic view of the adjustable-length proximity sensorprobe of FIG. 4;

FIGS. 6 through 8 are schematic views of adjustable-length proximitysensor probes according to other example embodiments of the presentinvention;

FIG. 9 is a schematic view of an adjustable-length proximity sensorprobe according to an example embodiment of the present invention withan integrated sensor for monitoring a parameter of motor performance;and

FIGS. 10 and 11 are schematic views of tips of subsea sensor probesaccording to other example embodiments of the present invention.

DETAILED DESCRIPTION

The present invention will now be described more fully hereinafter withreference to the accompanying drawings, which illustrate embodiments ofthe invention. This invention may, however, be embodied in manydifferent forms and should not be construed as limited to theillustrated embodiments set forth herein. Rather, these embodiments areprovided so that this disclosure will be thorough and complete, and willfully convey the scope of the invention to those skilled in the art.Like numbers refer to like elements throughout. Prime notation, if used,indicates similar elements in alternative embodiments.

Referring to FIG. 1, subsea motor assembly 10 is an example subseadevice, which illustrates example aspects of the present invention. Asillustrated in FIG. 1, adjustable-length sensor assemblies areintegrated within the penetrator assemblies and installed within subseamotor assembly 10. Adjustable length sensor assemblies are installed inother locations within the motor housing for directly monitoring aposition of a motor shaft

Subsea motor assembly 10 includes a motor case or other type of motorhousing 12. Motor shaft 14 is disposed at least partially within motorhousing 12 such that motor shaft 14 has an interior end 16 disposedwithin motor housing 12 and an exterior end 18 extending to an exteriorof motor housing 12. Exterior end 18 is operable to be coupled to apump, drilling motor, tractor, vibrator or other component (not shown)to be driven by the motor. In some embodiments, exterior end 18 iscoupled to a shaft 176 (see FIG. 2) of a booster pump 150 for providingartificial lift to facilitate extraction of fluids from a well. Rotor 22and stator 24 drive motor shaft 14 as is understood in the art.

Motor shaft 14 is supported by lower bearing assembly 30 and upperbearing assembly 32 along a longitudinal axis “A” when in a static statesuch that motor shaft 14 is stationary with respect to motor housing 12.Upper and lower bearing assemblies 30, 32 include both thrust and radialbearings for supporting axial and radial loads. In some embodiments, atleast some of the thrust and radial bearings are fluid film bearings,which support their loads on a thin layer of liquid or gas as indicatedabove. As understood by those skilled in the art, in some embodiments,motor shaft 14 rotates in a generally elliptical orbit about axis “A”when supported by fluid-film bearings. The extent or degree of theelliptical orbit can be dependent on a degree of wear of the fluid-filmbearings. As recognized by those skilled in the art, other types ofbearing assemblies are susceptible to non-circular orbits such astilt-pad bearings or active magnetic bearings. Bearing assemblies 30, 32are supported within motor housing 12 by respective base supports 36,38. In some embodiments, base supports 36, 38 are formed integrally withmotor housing 12, and in some embodiments base supports have arelatively large mass with respect to motor shaft 14.

To monitor a position of motor shaft 14, a plurality of proximity sensorprobe assemblies 100, 110, 112 are provided. Some of the proximitysensor assemblies 100 can be integrated into integrated penetrator andproximity sensor probe assemblies 102, 104 and 106, which penetratemotor housing 12 such that a portion of each integrated penetrator andproximity sensor probe assembly 102, 104, 106 is disposed on an interiorof the motor housing 12 proximate motor shaft 14, and a portion of eachpenetrator assembly is disposed on an exterior of motor housing 12. Asone skilled in the art will appreciate, a penetrator assembly generallyfacilitates passage of cables and other wiring through a bulkhead orinstrument package, and in some instances, with fewer seals than astandard connector set. The portions of the integrated penetrator andproximity sensor probe assembly 102, 104, 106 disposed on an exterior ofmotor housing 12 include respective electronics packages 108. Electronicpackages 108 enable communication of electrical power, signalconditioning, information and/or other media between the integratedpenetrator and proximity sensor probe assemblies 102, 104, 106 and othersubsea, down-hole or surface equipment, or other equipment exterior tomotor housing 12, through wired or wireless connections as will beappreciated by those skilled in the art. Other sensor assemblies includeadjustable-length proximity sensor probe assemblies 110 and 112, which,as illustrated in the example embodiment of FIG. 1, are disposed fullywithin the interior of motor housing 12.

A first pair of brackets 116, 118 is provided to maintain sensor tipassembly 120 of penetrator assembly 102 and the sensor tip assembly 122of proximity probe assembly 110 adjacent motor shaft 14 in an angularlydisplaced relationship to one another. In some embodiments, sensor tipassembly 120 and sensor tip assembly 122 are generally orthogonal to oneanother. Sensor tip assemblies 120, 122 are generally aligned along aradial axis with respect to motor shaft 14. Similarly, a second pair ofbrackets 126, 128 is provided to maintain sensor tip 130 of penetratorassembly 104 and sensor tip 132 of probe assembly 112 at adjacent motorshaft 14 in an orthogonal relationship to one another. Also, bracket 136is provided to maintain sensor tip 138 adjacent interior end 16 of motorshaft 14 in an orthogonal relation to sensor tip assemblies 130, 132.

In the embodiment illustrated in FIG. 1, sensor tip assemblies 120, 122,130, 132, 138 include a coil of an eddy current (EC) sensor. As oneskilled in the art will appreciate, the coil of an eddy current sensorgenerates a magnetic field, which in turn, generates small electriccurrents (called eddy currents) in a conductive target such as motorshaft 14. The eddy currents create a magnetic field that opposes themagnetic field generated by the coil, and the interaction of themagnetic fields is dependent upon a distance between the coil and thetarget. In other embodiments, alternate types proximity sensors ornon-contact position or range sensors may be employed such as LVDT's(linear variable differential transformers), capacitive sensors,photoelectric sensors, sonically operated devices and digital or opticalencoders.

Sensor tip assemblies 120, 122, 130, 132, 138 may be described as“pressure-compensated” at least since the sensor probe assemblies 100,110, 112 include features that are operable to permit a portion of anexterior or environmental pressure to which the sensor probe assemblies100, 110, 112 are exposed to be transmitted to interior portions of theproximity sensor tip assemblies 120, 122, 130, 132, 138 as described ingreater detail below. This pressure compensation offers protection tothe sensor tip assemblies 120, 122, 130, 132, 138 and the eddy currentsensor coils to facilitate operation within high pressure environments.

The interaction between the magnetic fields is detectable by electronicssuch as those electronics contained in electronic packages 108. In thismanner, sensor tips 120, 122, 130, 132 and 138 are operable to monitor aposition of motor shaft 14 along two sets of axially-spaced, x-y axesand along a z-axis. In the illustrated embodiment, each pair of sensortips associated with a particular x-y axis, e.g., sensor tips 120, 122and sensor tips 130, 132, are operatively coupled to a commonelectronics package 108 and the sensor tip 138 associated with thez-axis is operatively coupled to a separate electronics package. Inother embodiments, a single electronics package 108 is operativelyassociated with each of sensor tips 120, 122, 130, 132 and 138, and inother embodiments, each sensor tip 120, 122, 130, 132 and 138 isassociated with a separate electronics package 108.

An internal motor cavity 40 is defined between motor housing 12 andmotor shaft 14. In some embodiments, internal motor cavity 40 is filledwith a barrier fluid such as an oil, glycol, water or a combination ofdifferent fluids. Barrier fluids provide a clean operating environmentfor bearing assemblies 30, 32 and provide other benefits as appreciatedby those skilled in the art.

Internal motor cavity 40 is irregularly shaped, and in some locationsdefines a serpentine path between motor housing 12 and motor shaft 14.To properly position sensor tips 120, 122, 130, 132 and 138 adjacentmotor shaft 14, integrated penetrator and proximity sensor probeassemblies 102, 104, 106 and proximity sensor probe assemblies 110 and112 are configured to be flexible and adjustable in some embodiments. Insome instances, a straight and/or substantially rigid penetratorassembly 102 can be provided where sufficient space exists between motorhousing 12 and motor shaft 14. In other instances, a curved (flexible orsubstantially rigid) integrated penetrator and proximity sensor probeassembly 104 and/or proximity sensor probe assembly 112 is providedwhich curves to accommodate the position of internal motor componentssuch as stator 24 and base 38 without interfering therewith.

Referring to FIG. 2, subsea pump assembly 150 is another example subseadevice, which includes an integrated penetrator and proximity sensorprobe assembly 152. The integrated penetrator and sensor assembly 152includes a proximal penetrator housing 154, which is mounted directly toan exterior of pump housing 156 by fasteners 158. Proximal penetratorhousing 154 extends through an opening 160 defined through a wall ofpump housing 156 and forms a seal with the opening 160. Electronicspackage 162 is disposed within an interior of the pump housing 156. Inparticular, electronics package 162 is disposed within the proximalpenetrator housing 154 and within the opening 160 extending through thewall of the pump housing 156. This arrangement of the electronicspackage 162 within the opening 160 provides protection to theelectronics package 162 from damage by debris in the subsea environmentand permits the integrated penetrator and proximity sensor probeassembly 152 to maintain a low profile outside the pump housing 156.Electronics package 162 is disposed within an electronics housing 164,which defines a portion of proximal penetrator housing 154. Electronicshousing 164 is configured to maintain a nominal 1-atmosphere environmenttherein when exposed to an external pressure of about 1035 bar. In someembodiments, e.g., electronics housing 164 is configured to maintain apressure therein of less than 2 atmospheres when exposed to both a1-atmosphere ambient environment and a 1035 bar ambient environment.

As indicated by arrow 168, electronics package 162 is operable tocommunicate information related to parameters detected by the integratedpenetrator and proximity sensor probe assembly 152 to equipment exteriorto the integrated penetrator and proximity sensor probe assembly 152.For example, in some embodiments, electronics package 162 is operativelycoupled to a data acquisition (DAQ) module (not shown) for processingand/or storage of data provided by integrated penetrator and sensorassembly 152. In some embodiments, electronics package 162 is coupled tothe DAQ module through wired or wireless connections as will beappreciated by those skilled in the art.

Distal penetrator housing 166 extends from proximal penetrator housing154 into internal pump cavity 174 defined between pump housing 156 andpump shaft 176. Proximal and distal penetrator housing 154, 166 aresufficiently rigid such that proximity sensor tip assembly 178 issubstantially stationary with respect to pump housing 156 duringrotation or dynamic operation of pump shaft 176. In this manner,proximity sensor tip assembly 178 is cantilevered by a wall of the pumphousing 156, and is operable to sense a displacement of pump shaft 176between a static configuration wherein pump shall 176 is stationary withrespect to pump housing 156 and a dynamic configuration wherein pumpshaft 176 rotates within pump housing 156. Pump shaft 176 can be coupledto motor shaft 14 (FIG. 1) such that the pump shaft 176 is driven bymotor shaft 14 as recognized by those skilled in the art. In otherembodiments (see FIG. 3), portions of the distal penetrator housing 186are flexible and/or adjustable as indicated below.

Proximity sensor tip assemblies 178, 180 are generally aligned along aradial axis with respect to pump shaft 176 and in an angularly displacedrelation to one another. In some embodiments, proximity sensor tipassemblies 178 and 180 are substantially orthogonal to one another, andin other embodiments sensor tips 178 and 180 are angularly spaced by anangle in the range of about 25 degrees to about 155 degrees. Sensor tip180 is positioned at generally the same axial position along axis 182 assensor tip 178. In other embodiments, sensor tips 178, 180 are axiallydisplaced from one another by a predetermined distance such that aposition of motor shaft 176 along a pair of x-y axes is determinablefrom combined positional information provided by proximity sensor tipassemblies 178, 180. Proximity sensor tip assembly 180 is operativelycoupled to electronics package 162 through proximal penetrator housing154 of integrated penetrator and proximity sensor tip assembly 152 asindicated schematically. In other embodiments (not shown), proximitysensor tip assembly 180 is integrated into another integrated penetratorand proximity sensor tip assembly (not shown) that is independentlycoupled to the DAQ.

As shown in FIG. 3, an alternate embodiment of a subsea pump assembly184 includes an x-axis proximity sensor probe assembly 186 that isdistinct from electrical penetrator assembly 188. Electrical penetratorassembly 188 extends through opening 160 in pump housing 156 and isconnected to an exterior wall of the pump housing 156 with fasteners158′. Fasteners 158′ extend through an electronics housing 190, whichdefines a portion of proximal penetrator housing 154′. Electronicshousing 190 is configured to maintain a nominal 1-atmosphere environmenttherein when exposed to an external pressure of about 1035 bar.Electronics package 162′ is disposed within electronics housing 190 onan exterior of pump housing 156.

Proximity sensor probe assembly 186 extends through internal pump cavity174 along a serpentine path between pump housing 156 and mounting block191. A connector 192 is provided to couple proximity sensor probeassembly 186 to proximal penetrator housing 154′ and therebycommunicatively couple proximity sensor tip assembly 194 to electronicspackage 162′. Mounting block 191 includes a clamp, threads or anotherfixation mechanism to maintain proximity sensor tip assembly 194 ofproximity sensor probe assembly 186 at a fixed location with respect topump housing 156. An end of proximity sensor probe assembly 186 oppositeproximity sensor tip assembly 194 is also maintained at fixed locationwith respect to pump housing 156 by connector 192 or another fixationmechanism (not shown) provided on electrical penetrator assembly 188.The serpentine path taken between the opposing fixed ends of proximitysensor probe assembly 186 permits proximity sensor probe assembly 186 toaccommodate alternate motor, pump or other subsea device assemblies (notshown) having a rotating shaft spaced from a device housing by adifferent dimension. In some embodiments, a proximity sensor tipassembly 196 or a y-axis proximity sensor probe assembly is alsooperatively coupled to electronics package 162′ through electricalpenetrator assembly 188.

Referring now to FIG. 4A, integrated penetrator and proximity sensorprobe assembly 102 is arranged such that proximity sensor tip assembly120 is proximate motor shaft 14. Proximity sensor tip assembly 120includes proximity sensor cap 200 at distal or free end thereof. Asensing element 250 (see FIG. 4C) is disposed within proximity sensorcap 200 that is configured to produce a signal indicative of a distancebetween the proximity sensor cap 200 and motor shaft 14 or other targetproximate the proximity sensor cap 200. In this exemplary configuration,the sensing element 250 is an eddy current coil. The proximity sensortip assembly 120 also includes a mounting section 202 having distalthreads 204 and proximal threads 206. Distal threads 204 facilitatemounting the proximity sensor tip assembly 120 to structures such asmounting blocks 190 (FIG. 3) in other embodiments. The proximal threads206 facilitate mounting proximity sensor tip assembly 120 to distalportion 208 of penetrator housing 210. Proximal threads 206 are operableto adjust a gap “G” between proximity sensor cap 200 and motor shaft 14.Gap “G” represents a distance between a distal face “F” of the proximitysensor cap 200 and an outer surface “O” of the motor shaft 14. Whenmotor shaft 14 is in a static state such that motor shaft 14 isstationary with respect to motor housing 12, gap “G” can be adjustedsuch that proximity sensor cap 200 is sufficiently close to motor shaft14 to permit the sensing element 250 to detect motor shaft 14 andsufficiently remote from motor shaft 14 such that motor shaft 14 doesnot contact or damage proximity sensor cap 200 during dynamic operationof motor shaft 14 in which the motor shaft 14 may take a radiallyelliptical orbit (in an x-y plane) and/or take on a reciprocating motionin a longitudinal direction (along a z-axis). Once an appropriate gap“G” is achieved, a nut, clamp or other fixation mechanism (not shown) isapplicable to maintain the position of proximity sensor tip assembly 120with respect to distal portion 208 of penetrator housing 210.

Penetrator housing 210 includes distal portion 208 and proximal portion212. Distal portion 208 structurally and mechanically couples proximalportion 212 to proximity sensor tip assembly 120. In some embodiments,distal portion 208 is a substantially tubular member including exteriorthreads 214 at an end thereof for interfacing with proximal threads 206of proximity sensor tip assembly 120. In some embodiments, distalportion 208 is a generally straight and substantially rigid member. Inother embodiments, distal portion 208 is curved and/or flexible toaccommodate a serpentine interior motor cavity (see FIG. 1) Vents 218are provided through distal portion 208 of penetrator housing 210 suchthat an environmental fluid pressure, e.g., a fluid pressure of abarrier fluid within internal motor cavity 40 (FIG. 1), that is exteriorto distal portion 208 is transmissible to an interior of distal portion208 to equalize the pressure therein. Proximal portion 212 of penetratorhousing 210 includes a pair of o-rings 222 to form a seal with abulkhead or motor housing, e.g., motor housing 12 (FIG. 1). A flange 224includes fastener bores 226 extending therethrough and facilitatescoupling the proximal portion 212 of penetrator housing 210 to thebulkhead or motor housing.

Electronics package 108 is provided at an end of proximal portion 212 ofpenetrator housing 210. Electronics package 108 includes a housing thatis sufficiently sturdy to maintain a nominally 1-atmosphere (1.02 bar)pressure therein when integrated penetrator and proximity sensor probeassembly 102 is disposed in a high-pressure environment, e.g., submergedin a 1035 bar subsea environment. Signal transmission medium 230operatively couples electronics package to the sensing element 250 (FIG.4C) disposed within proximity sensor cap 200. In some embodiments,signal transmission medium 230 includes one or more electricalconductors such as a coaxial cable. In other embodiments, signaltransmission medium 230 includes fiber optics, sonic waveguides or othermedia configured to conduct power and/or information between electronicspackage 108 and proximity sensor cap 200. Signal transmission medium 230is of a sufficient length to provide slack for adjustment of gap “G” forpositioning the sensor tip assembly 120. The length of transmissionmedium 230 permits the transmission conductor to follow a serpentinepath through the sensor housing 232 along which the transmission medium230 is substantially spaced from a wall of the sensor housing 232. Inexample embodiments wherein the signal transmission medium 230 is anelectrical conductor, the length can be sufficiently short to prohibitcontact with the wall of the sensor housing 232 and thereby facilitateelectrical continuity through the signal transmission medium 230.

According to the example embodiment illustrated in FIG. 4A, theintegrated penetrator and proximity sensor probe assembly 102encapsulates the sensor probe assembly 100 (FIG. 1) therein. Sensorprobe assembly 100 includes sensor housing 232, signal transmissionmedium 230, fluid 236 and proximity sensor tip assembly 120. Accordingto other embodiments (not shown) sensor probe assembly 100 could bereplaced by other proximity sensor probes such as the proximity sensorprobes described below with reference to FIGS. 5 through 9. Sensorhousing 232 extends between proximal portion 212 of penetrator housing210 and proximity sensor tip assembly 120. Sensor housing 232 includes areinforced flexible tubing or hose through which signal transmissionmedium 230 extends. Opposing ends of sensor housing 232 are fixed toproximal portion 212 and proximity sensor tip assembly 120. Anextendable section of sensor housing 232 such as bellows 234 having aplurality of folds is provided to permit selectively lengthening andshortening of sensor housing 232 to thereby accommodate movement ofproximity sensor tip assembly 120 with respect to penetrator housing 210for adjustment of gap “G” for positioning the sensor tip assembly 120.

A liquid or substantially incompressible fluid 236 is disposed within afluid reservoir 238 defined on an interior sensor housing 232. Reservoir238 is in fluid communication with sensor tip assembly 120 as describedin greater detail below. Substantially incompressible fluid ishermetically sealed within sensor housing 232 and/or proximity sensortip assembly 120. In some embodiments, fluid 236 includes a dielectricfluid such as a gel, silicon oil, mineral oil, and monoethylene glycol.In some embodiments, a sufficient quantity of fluid 234 is providedwithin sensor housing 232 such that an internal pressure within sensorhousing 232 is greater than 1 atmosphere when integrated penetrator andproximity sensor probe assembly 102 is disposed in a 1 atmosphereenvironment. For example, an internal pressure may be about 1.05atmospheres.

A wall of sensor housing 232 includes a diaphragm or pliable membrane240. Pliable membrane 240 is operable to flex toward fluid 236 inresponse to an increase in an external environmental pressure to applyat least a portion of the external pressure to fluid 236. As illustratedin FIG. 4B, pliable membrane 240 is a mechanically thinned portion of ametallic wall of sensor housing 232. In other embodiments, pliablemembrane 240 includes alternate materials such as plastics orelastomers, e.g., as described with reference to FIG. 4D below.

As illustrated in FIG. 4C, mounting section 202 of proximity sensor tipassembly 120 may be filled with an epoxy 242 or other material. Aninterior channel 244 extends through the epoxy 242 from sensor housing232 to proximity sensor cap 200. Substantially incompressible fluid 236fills channel 244 such that sensor housing 232 is in fluid communicationwith interior portions of proximity sensor cap 200. Sensing element 250is enclosed or disposed within proximity sensor cap 200. In theillustrated embodiment, sensing element 250 is an eddy current coil, andproximity sensor cap 200 is constructed of a plastic, ceramic or otherelectrically insulating material capable of withstanding temperaturesand pressures encountered in subsea and wellbore environments. In otherembodiments, proximity sensor cap 200 is an integral end portion ofmounting section 202 that contains sensing element 250, and in otherembodiments, proximity sensor cap 200 is a separate and/or removablecomponent affixed to mounting section 202. Channel 252 extends intoproximity sensor cap 200 around signal transmission medium 230 andsensing element 250, and other crevices, cracks, gaps or voids 254 arepresent in the interior portions of proximity sensor cap 200.Substantially incompressible fluid 236 fills channel 252 and voids 254.Proximity sensor cap 200 is constructed such that an exterior face ofproximity sensor cap 200 is less pliable than pliable membrane 240 topermit at least a portion of the external pressure “E” to be applied tosubstantially incompressible fluid 236 via pliable member 240 toincrease the internal pressure of the proximity sensor cap 200 beforethe external pressure “E” crushes or damages the proximity sensor cap200 as described below.

Referring now to FIGS. 4A-4C and FIG. 1, in one example embodiment of anoperational procedure, integrated penetrator assembly and sensorassembly 102 is inserted into machine or motor housing 12 and affixedthereto with fasteners extending through fastener bores 226. A resultinggap “G” is evaluated by interpreting signals provided by the sensingelement 250 disposed within proximity sensor cap 200. According to anexample embodiment, in the event that gap “G” is determined to beunsatisfactory, integrated penetrator and proximity sensor probeassembly 102 is withdrawn from motor housing 12, and proximal threads206 are adjusted to appropriately move proximity sensor tip assembly 120with respect to flange 224. In response to the adjustment of internalthreads 206, bellows 234 unfolds or folds to appropriately extend orretract the extendable section of sensor housing 232. Integratedpenetrator and proximity sensor probe assembly 102 is re-inserted intomotor housing 12 and the resulting gap “G” is again evaluated to verifya satisfactory gap “G” has been achieved. According to otherembodiments, a location of brackets 116, 126 (FIG. 1) can adjusted toachieve a satisfactory gap “G.”

Subsea motor assembly 10 is then submerged into a high pressure, subseaor wellbore environment where an external pressure is as much as about1035 bar or more. In the event that motor housing 12 leaks and internalmotor cavity 40 is filled with high pressure fluid, an external pressure“E” established around integrated penetrator and proximity sensor probeassembly 102 increases. Vents 218 permit the high pressure fluid to flowinto penetrator housing 210 to equalize the pressure inside the walls ofthe distal portion 208 and to apply the external pressure “E” to sensorhousing 232. External pressure “E” is applied to pliable membrane 240,which bends or flexes inward toward substantially incompressible fluid236. In response to the flexing of pliable membrane 240, at least aportion of the external pressure “E” is applied to the substantiallyincompressible fluid 236 to increase the pressure within the fluidreservoir 238 and increase the internal pressure of sensor housing 232.Since the substantially incompressible fluid 236 extends into thechannel 252 and voids 254 in the proximity sensor cap 200, the increasedpressure of the substantially incompressible fluid 236 on interiorportions of the proximity sensor cap 200 at least partially balances theincreased external environmental pressure “E” applied to exteriorsurfaces of proximity sensor cap 200. Thus, proximity sensor cap 200 andsensing element 250 disposed therein are operable in the increasedenvironmental pressure “E.”

Substantially incompressible fluid 236 also beneficially protectselectrical connections and stabilizes the electrical parameters of anRLC circuit established by sensing element 250, signal transmissionmedium 230 and/or electronics in electronics package 108, thusfacilitating long-term sensor reliability and accuracy.

Sensing element 250 provides a signal indicative of a distance betweenthe proximity sensor cap 200 and motor shaft 14. Specifically, thesignal can be indicative of a distance between a reference point on theproximity sensor tip assembly, such as distal face “F” of the proximitysensor cap 200, and a reference point on the motor shaft 14, such asouter surface “O” of the motor shaft 14. The signal is transmitted toelectronics package 108, which in some embodiments, is interpreted tomeasure or determine a relative position of motor shaft 14 with respectto a preselected reference position. For example, a position of thelongitudinal axis “A” of the motor shaft 14 in dynamic operation thereofcan be measured relative to that of the position of the longitudinalaxis “A” of the motor shaft 14 in a static state, to thereby assess adegree of unbalance of subsea motor assembly 10 operating in the subseaenvironment. In other examples, it not necessary to correlate dynamicparameters of the motor shaft 14 to static parameters. Frequency contentand direction of vibration vectors may be assessed. This assessmentfacilitates identification of elliptical and/or reciprocating rotationalpatterns of the motor shaft 14 to assess the health of upper and lowerbearing assemblies 30, 32, and also facilitates diagnosis of problemssuch as erosion, imbalance and cracks in the motor shaft 14. Thisassessment thereby facilitates determining if repair or replacement ofthe subsea motor assembly 10 is required.

Referring to FIG. 4D, an alternate embodiment of a pliable membrane 240′is constructed of a reinforced flexible hose or tubing member. In someembodiments, the reinforced flexible tubing member can include a layerof rubber or plastic with an embedded or superimposed layer of a wovenor knitted mesh of wires or other reinforcing fibers. At least a portionof the wall of the sensor housing 232′ is formed by the pliable membrane240′ such that at least a portion of the external pressure “E” isapplied to the substantially incompressible fluid 236 in response topliable membrane 240′ flexing inward toward the substantiallyincompressible fluid 236. The resulting increase in the internalpressure on fluid 236 is applied to interior portions of proximitysensor cap 200 as described above.

Referring now to FIG. 5, proximity sensor probe 300 is depictedindependently of a penetrator assembly. In some embodiments, proximitysensor probe 300 could replace proximity sensor probe 100 in integratedpenetrator and proximity sensor probe assembly 102. Proximity sensorprobe 300 is an adjustable-length, pressure-compensated sensor probeincluding proximity sensor tip assembly 120 operably coupled to signaltransmission medium 230, and sensor housing 232 having bellows 234,pliable membrane 240 and substantially incompressible fluid 236 sealedtherein as described above. A connector or endcap 302 at a proximal endof sensor probe 300 seals substantially incompressible fluid withinsensor housing 232 and proximity sensor tip assembly 120. A pair ofleads 304 extends through end cap 302 and permit coupling signaltransmission medium 230 to a penetrator assembly, electronics package,data acquisition module or other device as desired.

In an embodiment of an operational procedure, the proximity sensor tipassembly 120 is mounted within a device housing such as motor housing 12(FIG. 1) or pump housing 156 (FIG. 2), e.g., with a bracket 118 (FIG. 1)or mounting block 191 (FIG. 3), to define an appropriate gap “G” (seeFIG. 4A) between the proximity sensor tip assembly 120 and the rotatingshaft, e.g., the motor shaft 14 (FIG. 1) or pump shaft 176 (FIG. 2). Alength of the sensor housing 232 is adjusted by expanding or contractingbellows to accommodate for a range of distances between the rotatingshaft 14, 176 and the wall of the device housing 12, 156. An end of thesensor housing 232 opposite the proximity sensor tip assembly 120, e.g.,an end adjacent endcap 302, is affixed to the wall of the device housing12, 156. Affixing the end of the sensor housing 232 with respect to thedevice housing 12, 156 facilitates connection of leads 304 to anelectronics package or other device as desired.

As illustrated in FIG. 6, proximity sensor probe 310 is similar toproximity sensor probe 300), but differs in that proximity sensor probe310 includes proximity sensor tip assembly 122 (see FIG. 1) rather thanproximity sensor tip assembly 120. Proximity sensor tip assembly 122facilitates coupling proximity sensor probe 310 to a bracket 118 (FIG.1), mounting block 191 (FIG. 3) or similar mounting device. Since sensortip assembly 122 does not necessarily couple to a penetrator housing,proximal threads 206 are not provided. Proximity sensor tip 122 is thussmaller and does not occupy so much of the internal cavity 40 (FIG. 1).

Referring now to FIGS. 7 and 8, proximity sensor probes 320 and 330 areadjustable-length, pressure-compensated sensor probes includingrespective proximity sensor tip assemblies 120, 122, signal transmissionmedia 230, substantially incompressible fluid 236 and endcaps 302 asdescribed above. Proximity sensor probes 320, 330 differ from proximitysensor probes 300, 310 in that housing 332 defines a bellows includingfolds extending along substantially an entire length of the housing 332.This arrangement provides additional flexibility and a length adjustingmechanism. In some embodiments, the folds in housing 332 permit housing332 to flex inwardly toward substantially incompressible fluid 236 suchthat the folds are operable to apply at least a portion of an externalpressure to the substantially incompressible fluid 236. In otherembodiments, a separate pliable membrane (not shown) is provided onhousing 332 or on endcap 302 to apply at least a portion of an externalpressure to the substantially incompressible fluid 236.

Referring now to FIG. 9, proximity sensor probe 350 is similar toproximity sensor probe 310 described above and includes a supplementalsensor 352 and supplemental signal transmission medium 354 disposedwithin substantially incompressible fluid 236. In some embodiments,supplemental sensor 352 is an acoustic or pressure sensor positionedadjacent sensing element 250 disposed within proximity sensor cap 200 ofproximity sensor tip assembly 122. Sensing element 250 can provideinductive, capacitive or another type of proximity sensing for directlymonitoring a position of motor shaft 14 (FIG. 1) as described above,while supplemental sensor 352 provides acoustic or pressure informationto facilitate an indirect assessment of equipment health. For example,detection of pressure fluctuations having a predetermined amplitude orexhibiting predetermined regular or irregular patterns can beindications of poor motor health.

Since the internal pressure of substantially incompressible fluid 236 isa function of an environmental pressure as described above, supplementalsensor 352 is operable to indirectly sense pressures and/or acousticwaves generated by motor shaft 14. The placement of supplemental sensor352 and supplemental signal transmission medium 354 within substantiallyincompressible fluid 236 protects these components from damage, and alsoallows supplemental sensor 352 to be positioned very near motor shaft 14(FIG. 1). Also, a particular supplemental sensor 352 can be associatedwith a particular sensing element 250 such that, in some embodiments,information provided by the supplemental sensor 352 can be used toconfirm a displacement detected by the associated sensing element 250.In various embodiments, the supplemental sensor 352 is a MEMS sensor, acapacitive sensor or a piezoelectric sensor. Also, in some embodiments,supplemental sensor 352 is a temperature sensor, a gyroscope, anaccelerometer, a digital compass, a microphone, a hydrophone and/orother types of sensors known in the art.

In one example embodiment of an operational procedure for assembling andusing a proximity sensor probe as illustrated in FIGS. 4A through 9, aproximity sensor probe is initially provided. The proximity sensorprobe, as initially provided, may or may not include features that areoperable to permit a portion of an environmental pressure to betransmitted to interior portions of a proximity sensor tip assemblythereof. Any voids, compressible materials and cavities where air orother compressible fluids can be contained are removed. A bellows orother extendable section is affixed to a sensor body surrounding asignal transmission medium. A pliable membrane is provided by removingmaterial or otherwise mechanically thinning a portion of a wall thesensor body. If desired, a supplemental sensor is positioned within thebody. The body is then filled with a substantially incompressible fluid,and all air or compressible fluids are forced out by the substantiallyincompressible fluid. The pressure of the substantially incompressiblefluid can be initially increased to above one atmosphere, oralternatively can be maintained below one atmosphere. The substantiallyincompressible fluid can then be sealed within the body with a connectoror endcap.

The proximity sensor probe can then be installed directly in machine ormotor similar to proximity sensor probe 110 (FIG. 1). Alternatively, theproximity sensor probe can be connected to a penetrator housing and/orelectronics package to form a penetrator assembly similar to integratedpenetrator and proximity sensor probe assembly 102 (FIG. 1). The sensorprobe can then be used to directly monitor a position of a rotatingshalt. If a position outside a predetermined set of parameters isdetected, a negative assessment of motor health may be made, and themotor may be refurbished or replaced before failure of the motor. Forexample, the position of the rotating shaft can be monitored to detect asynchronous vibration of the rotating shaft; a non-synchronous vibrationor asynchronous vibration of the rotating shaft; and/or asub-synchronous vibration of the rotating shaft. As appreciated by thoseskilled in the art, synchronous, non-synchronous and sub-synchronousvibrations can be indicators of various conditions of a rotating devicesuch as a cracked shaft, misalignment, bearing defects, electricalfaults, severe looseness, etc. The position of the rotating shaft can bemonitored during various stages of dynamic operation including startup,loading and sustained operation.

Referring now to FIG. 10, an alternate embodiment of a sensor tipassembly 400 is illustrated. Sensor tip assembly 400 includes anelongate threaded body 402, which facilitates mounting of sensor tipassembly 400 to a bracket 118 (FIG. 1) or mounting block 191 (FIG. 3). Aproximity sensor cap 404, in which sensing element 408 is at leastpartially contained, is disposed at one end of threaded body 402.Sensing element 408 is operatively coupled to leads 410 by a signaltransmission medium 412 extending through threaded body 402.Substantially incompressible fluid 236 is hermetically sealed withinthreaded body 402 and/or proximity sensor cap 404. Pliable membranes 414are disposed on lateral sides of threaded body to permit at least aportion of an external environmental pressure to be applied tosubstantially incompressible fluid 236 within threaded body 402. Inother embodiments, a pliable membrane (not shown) is disposed on alongitudinal end face of proximity sensor cap 404 as indicated by arrow416, and/or a longitudinal end face of connector or endcap 418 asindicated by arrow 420.

As illustrated in FIG. 11, an alternate embodiment of a sensor tipassembly 430 includes an elongate threaded body 432 having vents 434disposed therein. Vents 434 permit an environmental fluid to flow intothreaded body 432 and/or proximity sensor cap 404. The environmentalfluid can thus at least partially balance the internal and externalpressure experienced by proximity sensor cap 404, and thereby protectssensing element 408 disposed therein.

In the drawings and specification, there have been disclosed a typicalpreferred embodiment of the invention, and although specific terms areemployed, the terms are used in a descriptive sense only and not forpurposes of limitation. The invention has been described in considerabledetail with specific reference to these illustrated embodiments. It willbe apparent, however, that various modifications and changes can be madewithin the spirit and scope of the invention as described in theforegoing specification.

That claimed is:
 1. A rotating device operable in high pressureenvironments, the rotating device comprising: a device housing having anopening extending through a wall of the device housing; a rotating shaftat least partially disposed within the device housing such that aninternal cavity is defined between the device housing and the rotatingshaft; and at least one integrated penetrator and proximity sensor probeassembly operable to monitor a position of the rotating shaft withrespect to a preselected reference position, the at least one integratedpenetrator and proximity sensor probe assembly comprising: a proximalpenetrator disposed adjacent the opening in the wall of the devicehousing and forming a seal with the wall of the device housing about theopening, the proximal penetrator housing coupled to an exterior of thedevice housing; a distal penetrator housing extending from the proximalpenetrator housing into the internal cavity; a pressure-compensatedproximity sensor tip assembly disposed within the internal cavity andcoupled to the distal penetrator housing, the proximity sensor tipassembly having interior portions into which a portion of anenvironmental pressure within the internal cavity is transmissible andincluding a proximity sensor cap at an end thereof and a sensing elementdisposed at least partially within the proximity sensor cap, the sensingelement configured to produce a signal indicative of a distance betweena reference point on the proximity sensor tip assembly and a portion ofthe rotating shaft; a signal transmission medium operatively coupled tothe sensing element disposed within the proximity sensor cap andextending through the distal penetrator housing, the proximal penetratorhousing and the opening in the wall of the device housing to theexterior of the device housing to transmit the signal indicative of thedistance between the reference point on the proximity sensor tipassembly and the reference point on the rotating shaft to therebymeasure a position of the rotating shaft relative to a preselectedreference position.
 2. The rotating device according to claim 1, whereinthe at least one integrated penetrator and proximity sensor probeassembly further comprises a sensor housing connected to the proximitysensor cap and the proximal penetrator housing, the sensor housingdefining a fluid reservoir containing a substantially incompressiblefluid therein, the signal transmission medium extending through thefluid reservoir.
 3. The rotating device according to claim 2, whereinthe a distal penetrator housing includes vents defined therein such thatan environmental fluid pressure exterior to distal penetrator housing istransmissible to an interior of distal penetrator housing to equalizethe pressure therein.
 4. The rotating device according to claim 2,wherein the distal penetrator housing is cantilevered from the wall ofdevice housing and the proximity sensor tip assembly is supported at anend of the distal penetrator housing opposite the device housing.
 5. Therotating device according to claim 3, wherein the proximity sensor tipassembly is adjustably supported at the end of the distal penetratorhousing opposite the device housing to accommodate for a range ofadjustability in a gap between the proximity sensor cap and the rotatingshaft.
 6. The rotating device according to claim 4, wherein the sensorhousing includes an extendable section operable to selectively lengthenand shorten the sensor housing to thereby accommodate for adjustment ofthe sensor tip assembly.
 7. The rotating device according to claim 1,wherein the at least one integrated penetrator and proximity sensorprobe assembly further comprises an electronics package coupled to theproximal penetrator housing, the electronics package communicativelycoupled to the signal transmission medium and operable to enablecommunication of information between the integrated penetrator andproximity sensor probe assembly and other equipment exterior to thedevice housing.
 8. The rotating device according to claim 6, wherein theelectronics package is disposed on the exterior of the device housing.9. The rotating device according to claim 6, wherein the electronicspackage is disposed within the opening extending through the wall of thedevice housing.
 10. The rotating device according to claim 6, whereinthe electronics package is disposed in an electronics housing configuredto maintain a nominal 1-atmosphere environment therein when exposed toan external pressure of about 1035 bar.
 11. The rotating deviceaccording to claim 6, wherein the electronics package is furthercommunicatively coupled to an additional signal transmission medium thatis operatively associated with an additional proximity sensor tipassembly arranged to measure an additional position of the rotatingshaft relative to an additional preselected reference position.
 12. Therotating device according to claim 1, wherein the rotating devicecomprises a subsea pumping apparatus including an electric motor havinga motor shaft and a pump having a pump shaft operatively coupled tomotor shaft, and wherein the rotating shaft includes at least one of themotor shaft and the pump shaft.
 13. The rotating device according toclaim 1, wherein the distal penetrator housing are curved along aserpentine pathway through the internal cavity.
 14. An integratedpenetrator and proximity sensor probe assembly, operable to monitor aposition of a rotating target within a device housing and to communicateinformation related to the position through a wall of the devicehousing, the integrated penetrator and proximity sensor probe assemblycomprising: a proximal penetrator housing configured to form a seal withthe wall of the device housing about an opening extending through thewall of the device housing, the proximal penetrator housing operable tocouple to an exterior of the device housing; a distal penetrator housingextending from the proximal penetrator housing; a proximity sensor tipassembly coupled to an end of the distal penetrator housing opposite theproximal penetrator housing, the proximity sensor tip assembly includinga proximity sensor cap at an end thereof and a sensing element disposedat least partially within the proximity sensor cap, the sensing elementconfigured to produce a signal indicative of a distance between areference point on the proximity sensor tip assembly and a portion ofthe rotating target; a signal transmission medium operatively coupled tothe sensing element disposed within the proximity sensor cap andextending through the distal penetrator housing to the proximalpenetrator housing to transmit the signal indicative of the distance tothe proximal penetrator housing; an electronics package disposed withinthe proximal penetrator housing and communicatively coupled to thesignal transmission medium, the electronics package operable to receivethe signal indicative of the distance and operable to communicateinformation related to the distance to equipment exterior to theintegrated penetrator and proximity sensor probe assembly.
 15. Theintegrated penetrator and proximity sensor probe assembly according toclaim 14, further comprising a sensor housing disposed about the signaltransmission medium and connected to the proximity sensor tip assemblyand the proximal penetrator housing, the sensor housing defining a fluidreservoir containing a substantially incompressible fluid therein, thefluid reservoir in fluid communication with the proximity sensor cap.16. The integrated penetrator and proximity sensor probe assemblyaccording to claim 15, further comprising a supplementary sensordisposed within the sensor housing and submerged within theincompressible fluid, wherein the supplementary sensor comprises atleast one of the following: an acoustic sensor; a pressure sensor; atemperature sensor; a gyroscope; an accelerometer; a digital compass; amicrophone and a hydrophone.
 17. The integrated penetrator and proximitysensor probe assembly according to claim 16, wherein the supplementarysensor is communicatively coupled to the electronics package through asupplemental signal transmission medium.
 18. The integrated penetratorand proximity sensor probe assembly according to claim 14, wherein theproximal penetrator housing includes a flange extending laterally withrespect to the distal penetrator housing and the proximity sensor tipassembly such that the flange is configured to abut an exterior of awall of a device housing when the proximity sensor tip assembly and thedistal penetrator housing are inserted through an opening in the wall ofthe device housing.
 19. The integrated penetrator and proximity sensorprobe assembly according to claim 14, wherein the proximity sensor tipassembly is adjustably supported at the end of the distal penetratorhousing opposite the proximal penetrator housing device housing toaccommodate for a range of adjustability in a gap between the proximitysensor cap and the rotating target.
 20. The integrated penetrator andproximity sensor probe assembly according to claim 19, wherein the endof the distal penetrator housing opposite the proximal penetratorhousing includes threads along a length thereof, the proximity sensortip assembly including corresponding threads thereon engaged with thethreads on the distal penetrator housing, and wherein the a proximitysensor tip assembly further includes a locking member operable tomaintain a position of the proximity sensor tip assembly along thethreads on the distal penetrator housing.